Network farms are a cluster of servers that collaborate to provide an integrated service. Often, web sites are implemented as a network farm. Network farms often have dynamically changing scalability needs based on the nature and demand for the service the network farm provides. For example, e-commerce sites may often experience seasonal demand during certain holiday seasons during which gift giving and exchange is traditional. On-line trading sites may experience more demand at certain times of the day perhaps just after the market opens, just before the market closes, just after lunch. Credit card sites may experience monthly peaks just before monthly payments are due. News information sites may experience dramatic demand peaks as news-worthy events unfold.
Typically, such network farms build out enough capacity to handle the spikes in demand. The downside of this approach is that when the demand goes down, more servers are idling or at least significantly below capacity. Accordingly, excess capacity is wasted. The Application Request Routing is providing a set of APIs that can be used to address this problem by providing real-time traffic load information and dynamically changing the traffic routing rules to add or remove server resources.